Valve motor driving circuit based on frequency converter
By controlling the start-up of the electric valve motor with a frequency converter, the problems of high starting current and damage caused by aging of the motor are solved, and precise adjustment and protection are achieved.
Patent Information
- Application Number
- CN202520084631.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-14
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2035-01-14
AI Technical Summary
Existing electric valves have high starting current and long starting time for their motors, which leads to serious damage to the motor windings, insulation, and mechanical transmission components, and the problem worsens as the valves age.
The system adopts a connection structure between a frequency converter and a valve motor. The frequency converter controls the motor start-up, enabling precise speed adjustment and protection. It also detects overcurrent, overload, and overheating and takes protective measures accordingly.
It achieves precise adjustment of motor speed, reduces the impact on motor and valve mechanical parts, improves control accuracy and response speed, and protects motor and mechanical components.
Smart Images
Figure CN223744601U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to electric valve application technical field, concretely relates to a valve motor drive circuit based on frequency converter. BACKGROUND
[0002] Electric valve is widely used in modern enterprise, and most ordinary valves need to be configured with special valve control box, and usually one valve is configured with one valve control box.
[0003] The defects of prior art are that: since the motor is high torque equipment, the starting torque is particularly large, the starting current is too large, the starting time is long, the starting current generally reaches 7 times of the rated current of the motor, the motor starting is difficult, and the starting current increases with the aging of the valve.
[0004] Therefore, a valve motor drive circuit based on frequency converter is provided. UTILITY MODEL CONTENTS
[0005] The utility model discloses a valve motor drive circuit based on frequency converter, adopt the connection structure of frequency converter and valve motor, adopt frequency converter control to improve control precision, response speed, solve the problem that the existing technology directly starts, and the starting current is large and the starting process causes great damage to motor winding, insulation and mechanical transmission parts along with the aging of the valve.
[0006] In order to achieve the above object, the utility model adopts the technical scheme, the utility model provides a valve motor drive circuit based on frequency converter, including three -phase four -wire power supply, three -phase four -wire power supply includes A line, B line, C line and N line, A line, B line, C line connects power switch QA after being connected to the R contact, S contact and T contact of the top of frequency converter UF1 respectively, the V contact, U contact and W contact of the bottom of frequency converter UF1 are connected to the V pole, U pole and W pole of motor M after being connected to contactor KM1 linkage switch respectively.
[0007] As preferred, the V contact, U contact and W contact are connected to the W pole, U pole and V pole of motor M after being connected to contactor KM2 linkage switch.
[0008] As preferred, the frequency converter UF1 side is provided with SD contact, STF contact and MO contact, the STF contact is connected to the SD contact of the normally open switch of relay K1, and the MO contact is connected to the SD contact after being connected to the parallel connection of the first normally open switch of contactor KM1 and the first normally open switch of contactor KM2 and the series connection of the normally closed switch of relay K1.
[0009] As preferred, the T contact of the frequency converter UF1 is connected to the button SB1.
[0010] As preferred, the button SB1 is connected to the button SB2 in parallel with the second normally open switch of the contactor KM1, and then connected to the first normally closed switch of the contactor KM2, the coil of the contactor KM1, the normally closed SLO switch and the normally closed STO switch in series, and connected to the N line.
[0011] As preferred, the button SB1 is connected to the button SB3 in parallel with the second normally open switch of the contactor KM2, and then connected to the first normally closed switch of the contactor KM1, the coil of the contactor KM2, the normally closed SLC switch and the normally closed STC switch in series, and connected to the N line.
[0012] As preferred, the button SB1 is connected to the third normally open switch of the contactor KM1 in parallel with the third normally open switch of the contactor KM2, and then connected to the coil of the time relay KT in parallel with the normally closed switch of the time relay KT in series with the coil of the relay K1, and connected to the N line.
[0013] Compared with the prior art, the valve motor driving circuit based on the frequency converter has the advantages and positive effects that,
[0014] 1. The valve motor driving circuit based on the frequency converter can realize precise adjustment of the rotating speed of the valve motor, meet the fine control requirement of the valve opening degree under different working conditions, reduce the impact on the motor and the mechanical part of the valve, and strengthen the protection of the valve motor.
[0015] 2. The valve motor driving circuit based on the frequency converter adopts the connection structure of the frequency converter and the valve motor, adopts the frequency converter control to improve the control precision and response speed, and solves the problems of direct starting, large starting current and great damage to the motor winding, insulation and mechanical transmission components in the starting process caused by the aging of the valve in the prior art. BRIEF DESCRIPTION OF DRAWINGS
[0016] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.
[0017] Figure 1 It is a circuit diagram of a valve motor driving circuit based on a frequency converter. DETAILED DESCRIPTION
[0018] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.
[0019] In the following description, a lot of specific details are set forth in order to provide a thorough understanding of the present application, however, the present application can be practiced without resorting to the different ways described herein, therefore, the present application is not limited to the specific embodiments disclosed in the following description.
[0020] Embodiment 1, as shown in a valve motor drive circuit based on frequency converter, including three-phase four-wire power supply, the three-phase four-wire power supply includes A line, B line, C line and N line, A line, B line, C line connects the power supply after opening switch QA is connected to the R contact, S contact and T contact of the top of the frequency converter UF1, the V contact, U contact and W contact of the bottom of the frequency converter UF1 is connected to the V pole, U pole and W pole of the motor M after connecting the contactor KM1 linkage switch respectively. Figure 1
[0021] The V contact, U contact and W contact are connected to the W pole, U pole and V pole of the motor M after connecting the contactor KM2 linkage switch.
[0022] The side of the frequency converter UF1 is provided with SD contact, STF contact and MO contact, the STF contact is connected to the normally open switch of the relay K1 connected to the SD contact, the MO contact is connected to the SD contact after connecting the parallel connection of the first normally open switch of the contactor KM1 and the first normally open switch of the contactor KM2 and the series connection of the normally closed switch of the relay K1.
[0023] The front side of the T contact of the frequency converter UF1 is connected to the button SB1.
[0024] The button SB1 is connected to the button SB2 in parallel with the second normally open switch of the contactor KM1, and then connected to the N line in series with the first normally closed switch of the contactor KM2, the coil of the contactor KM1, the normally closed SLO switch and the normally closed STO switch.
[0025] The button SB1 is connected to the button SB3 in parallel with the second normally open switch of the contactor KM2, and then connected to the N line in series with the first normally closed switch of the contactor KM1, the coil of the contactor KM2, the normally closed SLC switch and the normally closed STC switch.
[0026] The button SB1 is connected to the third normally open switch of the contactor KM1 in parallel with the third normally open switch of the contactor KM2, and then connected to the N line in series with the parallel connection of the coil of the time relay KT and the normally closed switch of the time relay KT and the parallel connection of the coil of the relay K1.
[0027] Principle: the frequency converter is used to control the valve, the three-phase power supply is connected to the input terminal R, S and T of the frequency converter as power supply, the output U, V and W is connected to the motor M, the forward and reverse rotation is controlled through the contactor KM1 linkage switch and the contactor KM2 linkage switch.
[0028] The implementation process is:
[0029] 1. Valve opening process: press the button SB2 to open the valve button, the power supply is from the lower 6th terminal of the switch QA, through the button SB1, the button SB2, the first normally closed switch of the contactor KM2, into the coil of the contactor KM1, and then into the valve limit normally closed SLO switch and the closing torque normally closed STO switch, to form an electrical path into the N line, the contactor KM1 linkage switch is energized and attracted, the second normally open switch of the contactor KM1 is closed, and the circuit is self-locked at the same time; at the same time, the third normally open switch of the contactor KM1 is closed, the time relay KT is energized and acts, and the relay K1 is energized and acts, the normally open switch of the relay K1 is closed, the normally closed switch of the relay K1 is opened, the slow speed terminal of the frequency converter obtains a running signal, the U, V, W output terminals of the frequency converter output low frequency alternating current, and through the contactor KM1 to the valve motor, the valve motor rotates at low speed, the frequency of the alternating current output by the frequency converter gradually increases, and the motor speed starts to slowly increase.
[0030] When the time relay reaches the scheduled time, the time relay KT normally closed switch is opened, the relay K1 coil loses power, the relay K1 normally open switch is opened, the relay K1 normally closed switch is closed, the high speed terminal of the frequency converter is energized, the U, V, W output terminals of the frequency converter output high frequency alternating current, and through the contactor KM1 to the valve motor, the valve motor rotates at high speed. After the valve is opened to the limit, the open-to-limit limit switch normally closed SLO switch is opened, the KM1 contactor loses power, the relay K1 loses power at the same time, and at the same time, the high speed terminal MO and the low speed terminal STF of the frequency converter have no running command, and the valve motor stops rotating.
[0031] 2. Valve closing process: press the button SB3 to close the valve button, the power supply is from the lower 6th terminal of the switch QA, through the button SB1, the button SB3, the first normally closed switch of the contactor KM1, into the coil of the contactor KM2, and then into the valve closing limit normally closed SLC switch and the closing torque normally closed STC switch, to form an electrical path into the N line, the contactor KM2 linkage switch is energized and attracted to reverse, the second normally open switch of the contactor KM2 is closed, and the circuit is self-locked at the same time; at the same time, the third normally open switch of the contactor KM2 is closed, the time relay KT is energized and acts, and the relay K1 is energized and acts, the normally open switch of the relay K1 is closed, the normally closed switch of the relay K1 is opened, the slow speed terminal of the frequency converter obtains a running signal, the U, V, W output terminals of the frequency converter output low frequency alternating current, and through the contactor KM1 to the valve motor, the valve motor rotates at low speed, the frequency of the alternating current output by the frequency converter gradually increases, and the motor speed starts to slowly increase.
[0032] When the time relay reaches the appointed time, the time relay KT normally closed switch is opened, the relay K1 coil is de-energized, the relay K1 normally open switch is opened, the relay K1 normally closed switch is closed, the frequency converter fast terminal is energized, the frequency converter U, V, W output terminal outputs high frequency AC, and through the contactor KM2 to the valve motor, the valve motor rotates at high speed. When the valve is closed to the position, the closed to the position limit normally closed SLC switch is opened, the KM2 contactor is de-energized, the relay K1 is de-energized at the same time, and the high speed terminal MO and the low speed terminal STF of the frequency converter have no operation command, and the valve motor stops rotating.
[0033] The standard parts used in the utility model can be purchased from the market, the special-shaped parts can be ordered according to the description and the drawings, the specific connection mode of each part adopts the conventional means such as bolt, rivet and welding in the prior art, the mechanical, part and equipment adopt the conventional type in the prior art, the circuit connection adopts the conventional connection mode in the prior art, and the contents not described in detail in the specification belong to the prior art known by the person skilled in the art.
[0034] The above is only a preferred embodiment of the utility model, and does not limit other forms of the utility model, any person skilled in the art can change or modify the above disclosed technical content into equivalent embodiments applied to other fields, but any simple modification, equivalent change and modification made according to the technical essence of the utility model to the above embodiment still belong to the protection scope of the technical scheme of the utility model.
Claims
1. A frequency inverter based valve motor drive circuit, characterized by, The three-phase four-wire power supply includes A, B, C and N lines, the A, B and C lines are connected to the R, S and T contacts at the top of the frequency converter UF1 after the power supply self-switch QA, the V, U and W contacts at the bottom of the frequency converter UF1 are connected to the V, U and W poles of the motor M after the contactor KM1 linkage switch.
2. A frequency inverter based valve motor drive circuit as claimed in claim 1, wherein, The V, U and W contacts are connected to the W, U and V poles of the motor M after the contactor KM2 linkage switch.
3. A variable frequency drive based valve motor drive circuit as claimed in claim 1, wherein, The frequency converter UF1 is provided with SD, STF and MO contacts on one side, the STF contact is connected to the SD contact through the relay K1 normally open switch, and the MO contact is connected to the SD contact after the parallel connection of the first normally open switch of the contactor KM1 and the first normally open switch of the contactor KM2 and the series connection of the normally closed switch of the relay K1.
4. A variable frequency drive based valve motor drive circuit according to claim 3, wherein, The front side of the T contact of the frequency converter UF1 is connected to the button SB1.
5. A variable frequency drive based valve motor drive circuit according to claim 4, wherein, The button SB1 is connected to the button SB2 in parallel with the second normally open switch of the contactor KM1, and then connected to the N line in series with the first normally closed switch of the contactor KM2, the coil of the contactor KM1, the normally closed SLO switch and the normally closed STO switch.
6. A variable frequency drive based valve motor drive circuit according to claim 5, wherein, The button SB1 is connected to the button SB3 in parallel with the second normally open switch of the contactor KM2, and then connected to the N line in series with the first normally closed switch of the contactor KM1, the coil of the contactor KM2, the normally closed SLC switch and the normally closed STC switch.
7. A variable frequency drive based valve motor drive circuit as claimed in claim 6, wherein, The button SB1 is connected to the N line in series with the third normally open switch of the contactor KM1 and the third normally open switch of the contactor KM2, and then connected to the N line in series with the parallel connection of the coil of the time relay KT and the normally closed switch of the time relay KT and the parallel connection of the coil of the relay K1 and the normally closed switch of the relay K1.